---
name: "ClientData"
section: "3"
platform: "linux"
package: "libvolpack1-dev"
version: "1.0b3-10"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/ClientData"
---

# ClientData(3)

define a client data pointer

## NAME

vpSetClientData - define a client data pointer

## SYNOPSIS

\#include \<volpack.h\>

vpResult

**vpSetClientData(***vpc, client\_data***)**

-

  vpContext \**vpc;*

-

  void \**client\_data;*

## ARGUMENTS

- *vpc*

  VolPack context from **vpCreateContext.**

- *client\_data*

  Pointer to application-specific client data.

## DESCRIPTION

**vpSetClientData** is used to store a pointer to application-specific client data in the VolPack context.  This pointer is passed to some of the callback routines (see vpSetCallback(3)) to allow the application to define its own state variables.  The pointer is not used by VolPack.

## ERRORS

The return value is always VP\_OK.

## SEE ALSO

[VolPack(3)](/VolPack/3.md), vpCreateContext(3), vpSetCallback(3)